Method of fabricating a belt and a belt used to make bulk tissue and towel, and nonwoven articles and fabrics

ABSTRACT

In a method for manufacturing a belt and a belt for use in the production of bulk tissue and towel, and of nonwoven articles and fabrics, a polymeric resin material is applied onto the surface of a base substrate in a precise predetermined pattern which is to be imparted onto products manufactured with the belt. The polymeric resin material is deposited in droplets having an average diameter of 10μ (10 microns) or more. The polymeric resin material is then set by means appropriate to its composition, and, optionally, may be abraded to provide the belt with a uniform thickness, and a smooth, macroscopically monoplanar surface.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to the papermaking arts, andspecifically to the manufacture of paper tissue and toweling, which maybe collectively referred to as bulk tissue. The present invention alsorelates to the manufacture of nonwoven articles and fabrics by processessuch as hydroentanglement. In particular, the present invention relatesto belts, which have had a functional polymeric resin material depositedin precise preselected areas onto their base structures to fill thoseareas and, when desired, to form a layer of desired thickness thereover.Belts of this type are used in the manufacture of bulk tissue and towel,and of nonwoven articles and fabrics.

[0003] 2. Background of the Invention

[0004] Soft, absorbent disposable paper products, such as facial tissue,bath tissue and paper toweling, are a pervasive feature of contemporarylife in modern industrialized societies. While there are numerousmethods for manufacturing such products, in general terms, theirmanufacture begins with the formation of an embryonic paper web in theforming section of a paper machine. The embryonic paper web is thentransferred to a through-air-drying (TAD) fabric by means of an airflow, brought about by vacuum or suction, which deflects the web andforces it to conform, at least in part, to the topography of the TADfabric. Downstream from the transfer point, the web, carried on the TADfabric, passes through a through-air dryer, where a flow of heated air,directed against the web and through the TAD fabric, dries the web to adesired degree. Finally, downstream from the through-air dryer, the webmay be adhered to the surface of a Yankee dryer and imprinted thereon bythe surface of the TAD fabric, for further and complete drying. Thefully dried web is then removed from the surface of the Yankee dryerwith a doctor blade, which foreshortens or crepes the web and increasesits bulk. The foreshortened web is then wound onto rolls for subsequentprocessing, including packaging into a form suitable for shipment to andpurchase by consumers.

[0005] As noted above, there are many methods for manufacturing bulktissue products, and the foregoing description should be understood tobe an outline of the general steps shared by some of the methods. Forexample, the use of a Yankee dryer is not always required, as, in agiven situation, foreshortening may not be desired, or other means, suchas “wet creping”, may have already been taken to foreshorten the web.

[0006] The present application is concerned, at least in part, with theTAD fabrics used on the through-air dryer of a bulk tissue machine.Historically, TAD fabrics were woven from monofilament yarns in weavepatterns which provided their paper-supporting surfaces with knuckles,elevated relative to other areas on the surfaces, having relatively longfloats. Upon transfer from a forming fabric to the paper-contactingsurface of such a TAD fabric, the embryonic paper web would assume, atleast in part, the topography of that surface. As a consequence, theportions of the embryonic paper web deflected between the knucklesbecomes less dense relative to those on the knuckles, ultimately givingthe bulk tissue product softness and absorbency. Upon subsequentpressure transfer from the TAD fabric to the surface of a Yankee dryer,the knuckles on the paper-contacting surface of the TAD fabric imprintand densify those portions of the paper web lying thereon. Thisdensification, in turn, strengthens the bulk tissue product as a whole.The densification was typically enhanced by abrading or sanding thepaper-contacting surface of the TAD fabric to provide the knuckles withflat surfaces, thereby increasing the contact area between the paper weband the Yankee dryer, and enlarging the knuckle imprints to strengthenthe bulk tissue product further and to dry it more completely.

[0007] Driven by consumer interest in softer, more absorbent andstronger bulk tissue products, development initially centered on theweave patterns used to produce TAD fabrics. For example, in the nowexpired U.S. Pat. Nos. 4,191,609 and 4,239,065 to Trokhan, which areassigned to the Procter & Gamble Company of Cincinnati, Ohio, TADfabrics woven in weave patterns having nonnumerically consecutivewarp-pick sequences are shown. The disclosed weave patterns provide thepaper-supporting surfaces of the subject TAD fabrics with a plurality ofwicker-basket-like cavities disposed in a bilaterally staggered array,each such cavity being bounded by knuckles on the top-surface plane ofthe fabric. The TAD fabrics enable a bulk tissue product, having apatterned array of relatively closely spaced uncompressed pillowlikezones, each zone being circumscribed by a picket-like lineamentcomprising alternately spaced areas of compacted fibers and relativelynon-compacted fibers and formed by the top-surface-plane knuckles, to beproduced.

[0008] During the 1980's, an alternate means for providing a TAD fabricwith the equivalent of wicker-basket-like cavities was developed.Procter & Gamble's U.S. Pat. Nos. 4,528,239; 4,529,480; and 4,637,859 toTrokhan, which are among the earliest U.S. patent documents on thesemeans, show a TAD belt comprising a foraminous woven element, that is, awoven base fabric, having a coating of a polymeric resin material inpreselected areas. More specifically, the polymeric resin materialprovides the TAD belt with a macroscopically monoplanar, patterned,continuous network surface which serves to define within the TAD belt aplurality of discrete, isolated deflection conduits or holes, ratherthan wicker-basket-like cavities. To produce the TAD belt, theforaminous woven element is thoroughly coated with a liquidphotosensitive resin to a controlled thickness above its upper surface,and a mask or a negative having opaque and transparent regions whichdefine a desired pattern is brought into contact with the surface of theliquid photosensitive resin, and the resin is exposed to actinicradiation through the mask. The radiation, typically in the ultraviolet(UV) portion of the spectrum, cures the portions of the resin exposedthrough the mask, but does not cure the portions shadowed by the mask.The uncured resin is subsequently removed by washing to leave behind theforaminous woven element with a coating in the desired pattern formed bythe cured resin.

[0009] The seminal U.S. patent disclosing this method is Procter &Gamble's U.S. Pat. No. 4,514,345 to Johnson et al. In addition todisclosing the method for making the TAD belt described in the precedingparagraph, this patent also shows a belt in which the polymeric resinmaterial forms a plurality of discrete protuberances on its surface.That is to say, the pattern is the reverse of a continuous networkhaving holes. Instead, the pattern is of discrete areas which areoccluded or blocked by the polymeric resin material in an otherwise openforaminous woven element. Belts of this kind may be used in the formingsection of a bulk tissue machine to form embryonic paper webs havingdiscrete regions of relatively low basis weight in a continuousbackground of relatively high basis weight, as shown, for example, inProcter & Gamble's U.S. Pat. No. 5,277,761 to Van Phan et al. Belts ofthis kind may also be used to manufacture nonwoven articles and fabrics,which have discrete regions in which the density of fibers is less thanthat in adjacent regions, by processes such as hydroentanglement. Alsoin U.S. Pat. Nos. 6,080,691 and 6,120,642 to Kimberly-Clark there isdisclosed a papermaking fabric for producing a soft, bulky tissue webwherein the web contact surface is a three dimensional porous nonwovenmaterial. This material may be in the form of fiberous mats or web,extruded network or foams. Attachment of the porous nonwoven materialcan be by lamination, extrusion, adhesives, melt bonding, entanglement,welding, needling, nesting or layering.

[0010] In addition to discrete (non-continuous) and continuous networksof polymeric resin material on the foraminous woven element, the methoddisclosed in U.S. Pat. No. 4,514,345 to Johnson et al. may also be usedto manufacture belts having semicontinuous networks of polymeric resinmaterial. For example, Procter & Gamble's U.S. Pat. No. 5,714,041 toAyers et al. shows a belt, useful as a TAD fabric, having a framework ofprotuberances arranged in a semicontinuous pattern to provide asemicontinuous pattern of deflection conduits. By “semicontinuous” ismeant that each protuberance extends substantially throughout the beltin an essentially linear fashion, and that each protuberance is spacedapart from adjacent protuberances. As such, the protuberances may belines which are generally straight, parallel and equally spaced from oneanother, or may be in the shape of zigzags which are generally paralleland equally spaced from one another.

[0011] In some bulk tissue applications, press fabrics having acontinuous, semicontinuous or discrete network of polymeric resinmaterial on their paper-contacting surfaces are used. By “press fabric”is meant a fabric normally used on the press section of a paper machineand comprising a base fabric or other support structure and one or morelayers of staple fiber material attached to at least one side thereof.For example, Procter & Gamble's U.S. Pat. No. 5,556,509 to Trokhan etal. shows “press fabrics” having continuous and discrete networks ofpolymeric material on their paper-contacting surfaces and used to makebulk tissue products.

[0012] The method disclosed in U.S. Pat. No. 4,514,345, and therefinements thereto disclosed in subsequent Procter & Gamble U.S.patents, are quite elaborate and time-consuming. A more direct approachfor providing a forming, press or TAD fabric, or a fabric used in themanufacture of nonwoven articles and fabrics by processes such ashydroentanglement, with a coating of a polymeric resin material in theform of a continuous, semicontinuous or discrete network has long beensought in the industries concerned. The present invention satisfies thislong-felt need.

SUMMARY OF THE INVENTION

[0013] Accordingly, the present invention is a method for manufacturinga belt and a belt for use in the production of bulk tissue and towel,and of nonwoven articles and fabrics. The invention comprises a firststep of providing a base substrate for the belt.

[0014] Polymeric resin material is then deposited onto the basesubstrate in a precise predetermined pattern, which predeterminedpattern is to be imparted onto products manufactured with the belt. Thepolymeric resin material penetrates into the base substrate and, whendesired, forms a layer of desired thickness thereover. The polymericresin material is deposited in droplets having an average diameter of10μ (10 microns) or more, and is then set or fixed by appropriate means.Subsequently, the coating of polymeric resin material may optionally beabraded to provide it with a uniform thickness and a smooth,macroscopically monoplanar surface.

[0015] The present invention will now be described in more completedetail, with frequent reference being made to the figures identifiedbelow.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]FIG. 1 is a schematic view of an apparatus used to manufacturepapermaker's belts according to the method of the present invention;

[0017]FIG. 2 is a plan view of a completed belt as it would appear uponexit from the apparatus of FIG. 1;

[0018]FIG. 3 is a cross-sectional view taken as indicated in FIG. 2;

[0019]FIG. 4 is a plan view of a second embodiment of the belt;

[0020]FIG. 5 is a plan view of a third embodiment of the belt;

[0021]FIG. 6 is a plan view of a belt of the variety shown in FIG. 2having an additional pattern superimposed upon a pattern of discretepassages; and

[0022]FIG. 7 is a perspective view of a variety of representative shapesof the deposited material.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The method for fabricating a belt in accordance with the presentinvention begins with the provision of a base structure or substrate.Typically, the base substrate is a fabric woven from monofilament yarns.More broadly, however, the base substrate may be a woven, nonwoven orknitted fabric comprising yarns of any of the varieties used in theproduction of paper machine clothing or of belts used to manufacturenonwoven articles and fabrics, such as monofilament, plied monofilament,multifilament and plied multifilament yarns. These yarns may be obtainedby extrusion from any of the polymeric resin materials used for thispurpose by those of ordinary skill in the art. Accordingly, resins fromthe families of polyamide, polyester, polyurethane, polyaramid,polyolefin and other resins may be used.

[0024] Alternatively, the base substrate may be composed of meshfabrics, such as those shown in commonly assigned U.S. Pat. No.4,427,734 to Johnson, the teachings of which are incorporated herein byreference. The base substrate may further be a spiral-link belt of thevariety shown in many U.S. patents, such as U.S. Pat. No. 4,567,077 toGauthier, the teachings of which are also incorporated herein byreference.

[0025] Moreover, the base substrate may be produced by spirally windinga strip of woven, nonwoven, knitted or mesh fabric in accordance withthe methods shown in commonly assigned U.S. Pat. No. 5,360,656 toRexfelt et al., the teachings of which are incorporated herein byreference. The base substrate may accordingly comprise a spirally woundstrip, wherein each spiral turn is joined to the next by a continuousseam making the base substrate endless in a longitudinal direction.

[0026] The above should not be considered to be the only possible formsfor the base substrate. Any of the varieties of base substrate used bythose of ordinary skill in the paper machine clothing and related artsmay alternatively be used.

[0027] Once the base substrate has been provided, one or more layers ofstaple fiber batt may optionally be attached to one or both of its twosides by methods well known to those of ordinary skill in the art.Perhaps the best known and most commonly used method is that ofneedling, wherein the individual staple fibers in the batt are driveninto the base structure by a plurality of reciprocating barbed needles.Alternatively, the individual staple fibers may be attached to the basesubstrate by hydroentangling, wherein fine high-pressure jets of waterperform the same function as the above-mentioned reciprocating barbedneedles. It will be recognized that, once staple fiber batt has beenattached to the base substrate by either of these or other methods knownby those of ordinary skill in the art, one would have a structureidentical to that of a press fabric of the variety generally used todewater a wet paper web in the press section of a paper machine.

[0028] Alternatively still, the base substrate may be a structure whichhas been rendered impermeable to fluids, such as air and water, with acoating of a polymeric resin material, which at least partiallyimpregnates the structure and which may form a layer of a desiredthickness on one of its two sides. An impermeable base substrate may beused in the present invention in the manufacture of an embossing belt ofthe variety shown in U.S. Pat. No. 6,340,413, the teachings of which areincorporated herein by reference. The embossing belt disclosed thereinis essentially impermeable and comprises a rear layer and aweb-contacting layer, which has a large number of uniformly distributeddepressions and, positioned therebetween, surface portions for forming acorresponding relief pattern in a fibrous web passing through a presssection of a paper machine. The embossing belt also transfers theembossed fibrous web to the dryer section of the paper machine.

[0029] Furthermore, structures of this type, whether permeable or not,can have a random surface topography. This topography can be repeatedwithin a structure, or obviously, repeated in a subsequent structureproduced for the same paper, tissue or nonwoven production machine.Fabrics of this type are taught in U.S. Pat. Nos. 6,080,691 and6,120,642, the disclosures of which are incorporated herein byreference.

[0030] The belts manufactured in accordance with the present inventionmay be used on the forming, press or through air-drying sections of apaper machine, especially those producing tissue or towel products, oron a machine used to manufacture nonwoven articles and fabrics byprocesses such as hydroentanglement. Those having a needled batt-on-basesubstrate are most suitable for use on a press section, while thoselacking staple fiber batt may find use on any of these sections ormachines. In some cases, it may be necessary to apply an initial layeror additional batt to the structure after application of the resin. Insuch cases the patterned resin may lie below a layer of batt fibers.

[0031] Once the base substrate, with or without the addition of staplefiber batt material, has been provided, it is mounted on the apparatus10 shown schematically in FIG. 1. It should be understood that the basesubstrate may be either endless or seamable into endless form duringinstallation on a paper machine. As such, the base substrate 12 shown inFIG. 1 should be understood to be a relatively short portion of theentire length of the base substrate 12. Where the base substrate 12 isendless, it would most practically be mounted about a pair of rolls, notillustrated in the figure but most familiar to those of ordinary skillin the paper machine clothing arts. In such a situation, apparatus 10would be disposed on one of the two runs, most conveniently the top run,of the base substrate 12 between the two rolls. Whether endless or not,however, the base substrate 12 is preferably placed under an appropriatedegree of tension during the process. Moreover, to prevent sagging, thebase substrate 12 may be supported from below by a horizontal supportmember as it moves through apparatus 10.

[0032] Referring now more specifically to FIG. 1, where the basesubstrate 12 is indicated as moving in an upward direction through theapparatus 10 as the method of the present invention is being practiced,apparatus 10 comprises a sequence of several stations through which thebase substrate 12 may pass incrementally as a belt is being manufacturedtherefrom.

[0033] In the first station, the polymer deposition station 14, apiezojet array 16 mounted on transverse rails 18, 20 and translatablethereon in a direction transverse to that of the motion of the basesubstrate 12 through the apparatus 10, as well as therebetween in adirection parallel to that of the motion of the base substrate 12, isused to deposit polymeric in repeated steps to build up the desiredamount of resin material onto the base substrate 12 in a predeterminedpattern.

[0034] Alternatively, other means for depositing the small dropletsrequired for the practice of the present invention, as will be discussedbelow, may be known to those of ordinary skill in the art or may bedeveloped in the future, and may be used in the practice of the presentinvention. In addition, the deposit of the material need not only betraversing the movement of the base substrate but can be parallel tosuch movement, spiral to such movement or in any other manner suitablefor the purpose.

[0035] The polymeric resin material penetrates into the base substrate,and, when desired, forms a layer of a desired thickness thereover, inthe predetermined pattern. That pattern may be a continuous networkextending substantially throughout both dimensions of the surface of thebase substrate 12 and defining an array of discrete open areas which areto be the ultimate locations of a corresponding array of discrete holesor passages for fluid through the belt being manufactured from the basesubstrate 12, or on the surface of the belt of the base substrate 12. Itis also envisioned for some applications that the belt need not bepermeable. In this case the substrate may be a support base alreadyimpregnated with a resin, and having no fluid permeability or thesubstrate may be an extruded polymer film or even a metal band. Thediscrete open areas may form outlines or other representations offamiliar objects, such as clouds, flowers, swans or leaves, or ofcorporate or company logos, which are to appear in the desired array onthe product to be manufactured on the belt. Moreover, the array ofoutlines may be superimposed on a background array of smaller discreteholes.

[0036] Alternatively, the polymeric resin material may be deposited in asemicontinuous network, for example, a semicontinuous pattern extendingsubstantially throughout the base substrate 12 in an essentially linearfashion, thereby forming lines which are generally parallel and equallyspaced from one another. Such lines may be either straight, curved orzigzag. More generally, a semicontinuous network comprises straight orcurved lines, or lines having both straight and curved segments, whichare spaced apart from one another and do not cross one another.

[0037] Alternatively still, the polymeric resin material may bedeposited in an array of discrete locations. It should be appreciatedthat the polymeric resin material may be deposited in a manner formingan outline or other representation of a familiar object, such as acloud, flower, swan or leaf, or of a corporate or company logo, which isto appear in the desired array on the product to be manufactured on thebelt. Moreover, the array of outlines may be superimposed on abackground array of smaller discrete locations on which the polymericresin material is deposited.

[0038] In each case, the polymeric resin material impregnates and blocksthe passages through the base substrate 12, and, when desired, rises toa predetermined height above the surface of the base substrate 12, atthe locations where it is deposited. As such, the polymeric resinmaterial could ultimately reside entirely within the surface plane ofthe base substrate 12, even with the surface plane of the base substrate12, or above the surface plane of the base substrate 12.

[0039] The piezojet array 16 comprises at least one but preferably aplurality of individual computer-controlled piezojets, each functioningas a pump whose active component is a piezoelectric element. As apractical matter, an array of up to 256 piezo jets or more may beutilized, if the technology permits. The active component is a crystalor ceramic which is physically deformed by an applied electric signal.This deformation enables the crystal or ceramic to function as a pump,which physically ejects a drop of a liquid material each time anappropriate electric signal is received. As such, this method of usingpiezojets to supply drops of a desired material repeatedly so as tobuild up the desired amount of material in the desired shape in responseto computer-controlled electric signals is commonly referred to as a“drop-on-demand” method.

[0040] The degree of precision of the jet in depositing the materialwill depend upon the dimensions and shape of the structure being formed.The type of jet used and the viscosity of the material being appliedwill also impact the precision of the jet selected.

[0041] Referring again to FIG. 1, the piezojet array 16, starting froman edge of the base substrate 12, or, preferably, from a referencethread extending lengthwise therein, translates lengthwise and widthwiseacross the base substrate 12, while the base substrate 12 is at rest,deposits the polymeric resin material in the form of extremely smalldroplets having a nominal diameter of 10μ (10 microns) or more such as,of 50μ (50 microns), or 100μ (100 microns), in one of theabove-described patterns. The translation of the piezojet array 16lengthwise and widthwise relative to the base substrate 12, and thedeposition of droplets of the polymeric resin material from eachpiezojet in the array 16, are controlled by computer in a controlledmanner to produce the predetermined pattern of the polymeric resinmaterial in a controlled geometry in three planes length, width anddepth or height (x, y, z dimensions or direction) within, and, whendesired, on the base substrate 12. One or more passes over the basesubstrate 12 may be made by piezojet array 16 to deposit the desiredamount of material and to create the desired shape. In this regard, thedeposits can take any number of shapes as illustrated generally in FIG.7. The shapes can be square, round conical, rectangular, oval,trapezoidal etc. with a thicker base tapering upward. Depending upon thedesign chosen, the amount of material deposited can be layered indecreasing fashion as the jet repeatedly passes over the deposit area.

[0042] In the present invention, in which a piezojet array is used todeposit polymeric resin material onto or within selected areas of thesurface of the base substrate 12, the choice of polymeric resin materialis limited by the requirement that its viscosity be 100 cps (100centipoise) or less at the time of delivery, that is, when the polymericresin material is in the nozzle of a piezojet ready for deposition, sothat the individual piezojets can provide the polymeric resin materialat a constant drop delivery rate. In this regard, the viscosity of thepolymeric resin material at the point of delivery in conjunction withthe jet size is important in deferring the size and shape of thedroplets formed on the base substrate 12 and in time the resolution ofthe pattern ultimately achieved. Another requirement limiting the choiceof polymeric resin material is that it must partially set during itsfall, as a drop, from a piezojet to the base substrate 12, or after itlands on the base substrate 12, to prevent the polymeric resin materialfrom flowing and to maintain control over the polymeric resin materialto ensure its deposition in the desired pattern. Suitable polymericresin materials which meet these criteria are:

[0043] 1. Hot melts and moisture-cured hot melts;

[0044] 2. Two-part reactive systems based on urethanes and epoxies;

[0045] 3. Photopolymer compositions consisting of reactive acrylatedmonomers and acrylated oligomers derived from urethanes, polyesters,polyethers, and silicones; and

[0046] 4. Aqueous-based latexes and dispersions and particle-filledformulations including acrylics and polyurethanes.

[0047] As noted above, the piezojet array 16 is capable of supplying thepolymeric resin material in the form of extremely small droplets havingan average diameter of 10μ (10 microns) or more, so long as itsviscosity is less than 100 cps (100 centipoise) or less at the time ofdelivery. Moreover, the piezojet array 16 can deposit the polymericresin material with great precision one layer at a time, making itunnecessary to grind the surface of a layer formed thereby on the basesubstrate 12 to achieve a uniform thickness, and enables one of ordinaryskill in the art to control the z-direction geometry of the polymericresin material. That is to say, the piezojet array 16 can deposit thepolymeric resin material with such precision that the surface will bemonoplanar without having to be ground or, alternatively, that thesurface will have some predetermined three-dimensional structure.

[0048] That is to say by depositing the droplets in a repeating pattern,that being by layering one droplet on the top of the next, the height orz-direction of the polymeric resin material on the base substrate 12 iscontrolled and may be uniform, varied or otherwise adjusted as desired.Further, some of the individual piezojets in the piezojet array may beused to deposit one polymeric resin material, while others may be usedto deposit a different polymeric resin material, to produce a surfacehaving microregions of more than one type of polymeric resin material.It is understood that one or more passes of jet array 16 may be requiredto apply the required polymer resin material onto the base substrate 12.

[0049] Moreover, in an alternative embodiment of the present invention,the piezojet array 16 may include one or more bulk jets, which depositpolymeric resin material onto the base substrate 12, at a rate greaterthan that at which it can be deposited by piezojets. The choice of thepolymeric resin material to be deposited by the bulk jets is notgoverned by the viscosity requirement for the polymeric resin materialbeing deposited by the piezojets. As such, a wider variety of polymericresin materials, such as pdlyurethane and photosensitive resins, may bedeposited using the bulk jets. In practice, the bulk jets are used todeposit the “bulk” of the polymeric resin material onto the basesubstrate 12 at crude resolution, while the piezojets are used to refinethe details of the pattern produced by the polymeric resin material onthe base substrate 12 at higher resolution. The bulk jets may operateprior to or simultaneously with the piezojets. In this manner, theentire process of providing a base substrate 12 with a pattern of apolymeric resin material can proceed more quickly and efficiently.

[0050] It should be understood that the polymeric resin material needsto be fixed on or within the base substrate 12 following its depositionthereon. The means by which the polymeric resin material is set or fixeddepends on its own physical and/or chemical requirements. Photopolymersare cured with light, whereas hot-melt materials are set by cooling.Aqueous based latexes and dispersions are dried and then cured withheat, and reactive systems are cured by heat. Accordingly, the polymericresin materials may be set by curing, cooling, drying or any combinationthereof.

[0051] The proper fixing of the polymeric resin material is required tocontrol its penetration into and distribution within the base substrate12, that is, to control and confine the material within the desiredvolume of the base substrate 12. Such control is important below thesurface plane of the base substrate 12 to prevent wicking and spreading.Such control may be exercised, for example, by maintaining the basesubstrate 12 at a temperature which will cause the polymeric resinmaterial to set quickly upon contact. Control may also be exercised byusing such materials having well-known or well-defined curing orreaction times on base substrates having a degree of openness such thatthe polymeric resin material will set before it has time to spreadbeyond the desired volume of the base substrate 12.

[0052] When the pattern has been completed in a band between thetransverse rails 18, 20 across the base substrate 12, the base substrate12 is advanced lengthwise an amount equal to the width of the band, andthe procedure described above is repeated to produce the predeterminedpattern in a new band adjacent to that previously completed. In thisrepetitive manner, the entire base substrate 12 can be provided with thepredetermined pattern. Note the pattern can be random, a repeatingrandom pattern on a base substrate or such patterns that are repeatablefrom belt to belt for quality control.

[0053] Alternatively, the piezojet array 16, again starting from an edgeof the base substrate 12, or, preferably, from a reference threadextending lengthwise therein, is kept in a fixed position relative tothe transverse rails 18, 20, while the base substrate 12 moves beneathit, to deposit the polymeric resin material in the desired pattern in alengthwise strip around the base substrate 12. Upon completion of thelengthwise strip, the piezojet array 16 is moved widthwise on transverserails 18, 20 an amount equal to the width of the lengthwise strip, andthe procedure described above is repeated to produce the predeterminedpattern in a new lengthwise strip adjacent to that previously completed.In this repetitive manner, the entire base substrate 12 can be providedwith the predetermined pattern.

[0054] The surface is usually the contacting surface with the paper,tissue, towel or nonwoven producted to be produced. It is envisionedthat some products/processes will require this resin to be primarily onthe nonproduct contact surface. In this case fluid flow or mechanicalpressure differences that occur when the belt and the produced productsare in contact will still cause local density or texture differences.

[0055] At one end of the transverse rails 18, 20, a jet check station 22is provided for testing the flow of polymeric resin material from eachjet. There, the jets can be purged and cleaned to restore operationautomatically to any malfunctioning jet unit.

[0056] In the second station, the imaging/repair station 24, transverserails 26, 28 support a digital imaging camera 30, which is translatableacross the width of base substrate 12, and a repair-jet array 32, whichis translatable both across the width of the base substrate 12 andlengthwise relative thereto between transverse rails 26, 28, while thebase substrate 12 is at rest.

[0057] The digital imaging camera 30 views the deposited polymeric resinmaterial to locate any faulty or missing discrete elements or similarirregularities in a semicontinuous or continuous pattern producedthereby on the base substrate 12. Comparisons between the actual anddesired patterns are made by a fast pattern recognizer (FPR) processoroperating in conjunction with the digital imaging camera 30. The FPRprocessor signals the repair jet array 32 to deposit additionalpolymeric resin material onto the elements detected to be faulty ormissing. As before, at one end of the transverse rails 26, 28, arepair-jet check station 34 is provided for testing the flow of materialfrom each repair jet. There, each repair jet can be purged and cleanedto restore operation automatically to any malfunctioning repair jetunit.

[0058] In the third station, the optional setting station 36, transverserails 38, 40 support a setting device 42, which may be required to setthe polymeric resin material being used. The setting device 42 may be aheat source, for example, an infrared, hot air, microwave or lasersource; cold air; or an ultraviolet or visible light source, the choicebeing governed by the requirements of the polymeric resin material beingused.

[0059] Finally, the fourth and last station is the optional grindingstation 44, where an appropriate abrasive is used to provide anypolymeric resin material above the surface plane of the base substrate12 with a uniform thickness and a smooth, macroscopically monoplanarsurface. The optional grinding station 44 may comprise a roll having anabrasive surface, and another roll or backing surface on the other sideof the base substrate 12 to ensure that the grinding will result in auniform thickness and a smooth, macroscopically monoplanar surface.

[0060] As an example, reference is now made to FIG. 2, which is a planview of a completed belt 50 as it would appear upon exit from optionalsetting station 36 and the optional grinding station 44 of apparatus 10.The belt 50 has a coating of polymeric resin material 52 except for aplurality of discrete holes 54 in a predetermined pattern. A portion ofa permeable base substrate 12, which comprises a system ofmachine-direction (MD) yarns 56 interwoven with a system ofcross-machine-direction (CD) yarns 58, is visible in each of thediscrete holes 54.

[0061]FIG. 3 is a cross-sectional view of a completed belt 50 taken asindicated in FIG. 2. In this example, polymeric resin material 52 formsa layer of a desired thickness over the base substrate 12, except forthe areas represented by the discrete passages 64.

[0062] Alternative embodiments of the belt are shown in FIGS. 4 and 5.FIG. 4 is a plan view of a belt 60 whose base substrate 12 has aplurality of discrete areas 62 of polymeric resin material in apredetermined array. Such a belt 60 may be used in the forming sectionof a papermaking machine.

[0063]FIG. 5 is a plan view of a belt 70 having a semicontinuous networkof polymeric resin material on its surface. The semicontinuous networkextends substantially throughout the belt 70 in an essentially linearfashion. Each portion 72 of the semicontinuous network extends in asubstantially straight line, which may zigzag to some extent, parallelto others making up the network. Each portion 72 is of polymeric resinmaterial.

[0064]FIG. 6 is a plan view of a belt 80 of the variety shown in FIG. 2having an additional pattern superimposed upon a pattern of discretepassages 82. The additional pattern 84, which is a logo, but which mayalso be a familiar object, may also be repeated in a desired array onthe belt 80. A portion of the permeable base substrate 12 is visible ineach of the discrete passages 82, as well as in the additional pattern84.

[0065] In an alternate embodiment of the present invention, the polymerdeposition station 14, the imaging/repair station 24, and the settingstation 36 may be adapted to produce a belt from the base substrate 12in a spiral technique, rather than indexing in the cross-machinedirection as described above. In a spiral technique, the polymerdeposition station 14, the imaging/repair station 24, and the settingstation 36 start at one edge of the base substrate 12, for example, theleft-hand edge in FIG. 1, and are gradually moved across the basesubstrate 12, as the base substrate 12 moves in the direction indicatedin FIG. 1. The rates at which the stations 14, 24, 36 and the basesubstrate 12 are moved are set so that the pattern desired in thefinished belt is spiralled onto the base substrate 12 in a continuousmanner. In this alternative, the polymeric resin material deposited bythe polymer deposition station 14, and imaging/repair station 24 may bepartially set or fixed as each spiral passes beneath the setting device42, and completely set when the entire base substrate 12 has beenprocessed through the apparatus 10.

[0066] Alternatively, where the piezojet array 16 deposits the polymericresin material in the desired pattern in a lengthwise strip around thebase substrate 12, the imaging/repair station 24 and the setting station36 may also be kept in a fixed position aligned with the piezojet array16, while the base substrate 12 moves beneath them, so that the patterndesired in the finished belt is applied to a lengthwise strip around thebase substrate 12. Upon completion of the lengthwise strip, the piezojetarray 16, the imaging/repair station 24 and the setting station 36 aremoved widthwise an amount equal to the width of the lengthwise strip,and the procedure is repeated for a new lengthwise strip adjacent tothat previously completed. In this repetitive manner the entire basestructure 12 can be completely coated.

[0067] Furthermore, the entire apparatus can remain in a fixed positionwith the material processed. It should be noted that the material neednot be a full width belt but can be a strip of material such as thatdisclosed in U.S. Pat. No. 5,360,656 to Rexfelt, the disclosure of whichis incorporated herein by reference, and subsequently formed into a fullwidth belt. The strip can be unwound and wound up on a set of rollsafter fully processing. These rolls of belting materials can be storedand can then be used to form an endless full width structure using, forexample, the teachings of the immediately aforementioned patent.

[0068] Modifications to the above would be obvious to those of ordinaryskill in the art, but would not bring the invention so modified beyondthe scope of the appended claims. In particular, while piezojets aredisclosed above as being used to deposit the polymeric resin material inpreselected locations on the base substrate, other means for depositingdroplets thereof in the size range desired may be known to those ofordinary skill in the art or may be developed in the future, and suchother means may be used in the practice of the present invention. Forexample, in processes requiring a relatively larger scale pattern suchthat the final elements such as round hemispheres, a relatively large,even a single resin deposition nozzle can comprise the entire jet array.The use of such means would not bring the invention, if practicedtherewith, beyond the scope of the appended claims.

What is claimed is:
 1. A method for manufacturing a belt for use in theproduction of bulk tissue and towel, and of nonwoven articles andfabrics, said method comprising the steps of; a) providing a basesubstrate for the belt; b) depositing polymeric resin material onto saidbase substrate in a controlled manner so as to control the x, y, zdimensions of the material deposited to create a predetermined patternin droplets; and c) at least partially setting said polymeric resinmaterial.
 2. A method as claimed in claim 1 wherein said droplets havean average diameter of 10μ (10 microns) or more.
 3. A method as claimedin claim 1 wherein steps b) and c) are performed sequentially onsuccessive bands extending widthwise across said base substrate.
 4. Amethod as claimed in claim 1 wherein steps b) and c) are performedsequentially on successive strips extending lengthwise around said basesubstrate.
 5. A method as claimed in claim 1 wherein steps b) and c) areperformed spirally around said base substrate.
 6. A method as claimed inclaim 1 wherein, in step b), said predetermined pattern comprises aplurality of discrete locations set forth in a predetermined array.
 7. Amethod as claimed in claim 1 wherein, in step b), said predeterminedpattern comprises a continuous network defining a plurality of discreteopen areas in a predetermined array.
 8. A method as claimed in claim 1wherein, in step b), said predetermined pattern comprises asemicontinuous network extending substantially throughout said basesubstrate.
 9. A method as claimed in claim 1 wherein, in step b), saidpolymeric resin material penetrates into said base substrate.
 10. Amethod as claimed in claim 1 wherein, in step b), said polymeric resinmaterial forms a uniform or random pattern layer of desired thicknessover said base substrate.
 11. A method as claimed in claim 1 wherein, instep b), said polymeric resin material is deposited by a piezo-jetmeans.
 12. A method as claimed in claim 1 wherein, in step b), saidpolymeric resin material is deposited by a piezo-jet array comprising aplurality of individual computer-controlled piezo-jets.
 13. A method asclaimed in claim 1 further comprising, between steps b) and c), thesteps of: i) checking the actual pattern of said polymeric resinmaterial to measure conformity to said predetermined pattern to measureconformity to said predetermined pattern; and ii) repairing said actualpattern of said polymeric resin material to eliminate departures fromsaid predetermined pattern.
 14. A method as claimed in claim 13 whereinsaid checking step is performed by a fast pattern recognizer (FPR)processor operating in conjunction with a digital imaging camera.
 15. Amethod as claimed in claim 14 wherein said repairing step is performedby a repair-jet array coupled to said FPR processor.
 16. A method asclaimed in claim 1, wherein said polymeric resin material is selectedfrom the group consisting of:
 1. hot melts and moisture-cured hot melts;2. two-part reactive systems based on urethanes and epoxies; 3.photopolymer compositions consisting of reactive acrylated monomers andacrylated oligomers derived from urethanes, polyesters, polyethers, andsilicones; and
 4. aqueous-based latexes and dispersions andparticle-filled formulations including acrylics and polyurethanes.
 17. Amethod as claimed in claim 1 wherein said curing step is performed byexposing said polymeric resin material to a heat source.
 18. A method asclaimed in claim 1 wherein said curing step is performed by exposingsaid polymeric resin material to cold air.
 19. A method as claimed inclaim 1 wherein said curing step is performed by exposing said polymericresin material to actinic radiation.
 20. A method as claimed in claim 1wherein a first polymeric resin material is deposited and a secondpolymeric resin is deposited which is different from the first polymericresin material.
 21. A method as claimed in claim 10 wherein saidpolymeric resin material is deposited in a uniformly thick layer havinga monoplanar surface.
 22. A method as claimed 10 wherein said polymericresin material is deposited in a nonuniformly thick layer having asurface with a three-dimensional structure.
 23. A method as claimed inclaim 1 further comprising the step of depositing a polymeric resinmaterial onto said base substrate in said predetermined pattern with abulk jet to accelerate the manufacture of said belt.
 24. A method asclaimed in claim 23 wherein said depositing step is carried out prior tostep b).
 25. A method as claimed in claim 23 wherein said depositingstep is carried out simultaneously with step b).
 26. A method as claimedin claim 1 further comprising the step of abrading said polymeric resinmaterial deposited on said base substrate to provide said polymericresin material with a uniform thickness and a smooth, macroscopicallymonoplanar surface.
 27. A method as claimed in claim 1 which includesthe step of providing a base substrate taken from the group consistingessentially of woven, nonwoven, sprial formed, spiral-link, knitted,mesh or strips of material which are ultimately wound to form a belthaving a width greater than a width of the strips.
 28. A belt for use inthe production of bulk tissue and towel, and of nonwoven articles andfabrics, said belt being made in a manner comprising the steps of: a)providing a base substrate for the belt; b) depositing polymeric resinmaterial onto said base substrate in a controlled manner so as tocontrol the x, y, z dimensions of the material deposited to create apredetermined pattern in droplets; and c) at least partially settingsaid polymeric resin material.
 29. A belt as claimed in claim 28 whereinsaid droplets have an average diameter of 10μ (10 microns) or more. 30.A belt as claimed in claim 29 wherein steps b) and c) are performedsequentially on successive strips extending lengthwise around said basesubstrate.
 31. A belt as claimed in claim 28 wherein steps b) and c) areperformed sequentially on successive strips extending lengthwise aroundsaid base substrate.
 32. A belt as claimed in claim 28 wherein steps b)and c) are performed spirally around said base substrate.
 33. A belt asclaimed in claim 28 wherein, in step b), said predetermined patterncomprises a plurality of discrete locations set forth in a predeterminedarray.
 34. A belt as claimed in claim 28 wherein, in step b), saidpredetermined pattern comprises a continuous network defining aplurality of discrete open areas in a predetermined array.
 35. A belt asclaimed in claim 28 wherein, in step b), said predetermined patterncomprises a semicontinous network extending substantially throughoutsaid base substrate.
 36. A belt as claimed in claim 28 wherein, in stepb), said polymeric resin material penetrates into said base substrate.37. A belt as claimed in claim 28 wherein, in step b), said polymericresin material forms a uniform or random pattern layer of desiredthickness over said base substrate.
 38. A belt as claimed in claim 28wherein in step b), said polymeric resin material is deposited by apiezo-jet means.
 39. A belt as claimed in claim 28 wherein, in step b),said polymeric resin material is deposited by a peizo-jet arraycomprising a plurality of individual computer-controlled piezo jets. 40.A belt as claimed in claim 28, wherein said polymeric resin material isselected from the group consisting of:
 1. hot melts and moisture-curedhot melts;
 2. two-part reactive systems based on urethanes and epoxies;3. photopolymer compositions consisting of reactive acrylated monomersand acrylated oligomers derived from urethanes, polyesters, polyethers,and silicones; and
 4. aqueous-based latexes and dispersions andparticle-filled formulations including acrylics and polyurethanes.
 41. Abelt as claimed in claim 28 wherein a first polymeric resin material isdeposited and a second polymeric resin material is deposited which isdifferent from the first polymeric resin material.
 42. A belt as claimedin claim 37 wherein said polymeric resin material is deposited in auniformly thick layer having a monoplanar surface.
 43. A belt as claimedin claim 37 wherein said polymeric resin material is deposited in anonuniformely thick layer having a surface with a three-dimensionalstructure.
 44. A belt as claimed in claim 28 further comprising the stepof depositing a polymeric resin material onto said base substrate insaid predetermined pattern with a bulk jet to accelerate the manufactureof said belt.
 45. A belt as claimed in claim 28 wherein said depositingstep is carried out prior to step b).
 46. A belt as claimed in claim 28wherein said depositing step is carried out simultaneously with step b).47. A belt as claimed in claim 28 further comprising the step ofabrading said polymeric resin material deposited on said base substrateto provide said polymeric resin material with a uniform thickness and asmooth, macroscopically monoplanar surface.
 48. A belt as claimed inclaim 28 further comprising the step of providing a base substrate takenfrom the group consisting essentially of woven, nonwoven, spiral formed,spiral-link, knitted, mesh or strips of material which are ultimatelyspiral wound to form a belt having a width greater than a width of thestrips.